Imake has asked me on several occasions to start a thread on this subject given my background as a central heating installer and Oftech registered oil burner technician so here goes. I'm sure there are a good few people out there already using Bio either as a blend with kero and some full B100. Given that Kero is fast heading for €1 a litre it makes sense that we burn Biodiesel in our central heating boilers to heat our homes. Some other people on this forum have constructed boilers and are heating their homes from yellow grease in Ozzirt style burners and there is great merit in their work and what they have already achieved. By starting this thread we can exchange our own individual experiences and therefore pass on some helpful advice to would be users of B100 or a lesser percentage depending on what goes well for each situation.

The greatest percentage of burners on oil boilers in Ireland are made by Riello which is an Italian company. They are at the forefront of oil and gas burner technology and its a vote of confidence in their technology that the three main boiler manufacturers in Ireland use their burners. They are a reliable and mostly trouble free burner with good longetivity and with a bit of luck one should get anything from 20m to 30 years out of a burner provided it is regularly serviced and the controls set at their correct settings. When these burners first appeared on the Irish market in the late sixties and early seventies it was nearly all diesel or to give it its correct title 35 second oil that was consumed in them. It is the equivalent of agricultural diesel today but was less refined and did not have the advantages of some of the additives in todays diesel, it for instance much more likely to freeze in those days if the temp went below zero and unless your settings were as the manufacturers recommended it was prone to misfiring and creating soot and therefore a lot of black smoke which invariably did not please the neighbours.

Slowly through the eighties and into the nineties Kerosene or 28 second oil began to be used much more and with the advent of indoor oil boilers low level flues were introduced and eventually the twin wall balanced flue which is most common in todays boilers. Kerosene proved a godsend to these boiler manufacturers and despite being slightly dearer than diesel heating oil it allowed them to design boilers which could be placed under a worktop in a kitchen or utility situation just like a washing machine or dryer. This led to more efficiency as it eliminated long pipe runs from outside boiler houses and therefore less fuel was being used. Through the nineties and the noughties boiler efficiency has improved way beyond the early days and now it is the norm to have todays condensing boilers giving efficiency levels of 94 to 97%.

I have a lot of burners around my garage and Im lucky in that I can try different componenmts and settings to see which set up gives me the best results. Early on I favoured the Riello 3G as it was the burner which was compatable with my cast iron boiler but there were a few hiccups like misfiring and excess smoke which however I tried to eliminate I was never entirely happy with. Eventually I swithched over to a brand new Riello RDB which is a relatively new model of burner and I have to say that from the moment I fired it up that I have been very impressed with its overall performance. All the components are standard at present, I admit that the oil pump may have to be changed for the Bio one when the seals break down but at the moment after three months of constant use there are not signs that this is about to happen. Initally when one fires these burners up on Biodiesel there will be a bit of fluttering etc. as the characteristics of the oils are different with Bio being more viscous than kero. It is imperative to have an oil pressure gauge on the oil pump in order to monitor the pump pressure settings. Together with the air control damper these are the two most important settings on a pressure jet burner and there is no compromise on this as far as I am concerned. If you start making adjustments to the ouil pump pressure settings without having a pressure gauge on you are just asking for trouble. Normally the pressure settings are between 7 and 10 bar depending on the boiler make and size. Because 28 sec. Kerosene is so fluid and less viscous than 35 sec oil it was more tolerant of lower pressure settings as it took less pressure to atomise the oil and depending on the make and design of the oil nozzle was easier to ignite and retain a stable flame. Biodiesel is harder to ignite than either of the two fuels already mentioned and therefore the design of the nozzle is critical to first and every time firing/ignition. You will find relevant information on nozzles on several sites including make bio at home.org I increased the oil pressure setting on my burner fron 8 to 9 bar and straight away the flame was more stable and constant with less spluttering, minor tweaking of the air damper control may be necessary. If you havent a flue gas analyser the objective is to get you burner as lean and clean as possible so therefore it is imperative that you take a close look at what is coming out of your flue because if there is any hint of smoke regardless of colour this is a clear indication that it is not burning cleanly and that the fuel /air mix needs to be readjusted to get a clean burn. Black smoke means not enough air. white smoke too much air but this is all relative to your oil pump pressure setting. This is where the oil pressure gauge comes into its own because a half turn of the pressure setting screw on the oil pump can increase/decrease the pressure settings by half a bar and this can have an adverse affect on the atomisation of the oil. Generally I find that a Danfoss .75 Hollow nozzle with an 80 degree spray pattern works best for me. While a solid pattern nozzle will fire it is generally considered that the Hollow pattern is more suitable for Biodiesel. You may find that after the first couple of weeks while you are tweaking the settings that a very light crust of carbon may build up on the inners of the blast tube, it is imperative that the tube is taken off and scraped clean as the flame pattern can change for the worse if the inner cone of the blast tube is not clean and true. Hope this helps for now...........

Great post Crazyhorse, very useful. I'd love to be using bio to heat the house, I've got the oil but I don't have the time to make the bio. I'm struggling to keep up with enough to keep the van and the car going at the moment.

Most householders who have oil central heating would have a 1000lt minimum oil storage tank. In recent years due to oil getting stolen out of oil tanks some people have begun to store their tanks inside in close proximity to the oil boiler. This is all very well provided safety regulations regarding minimum distance from boiler and some other factors are maintained but for most people the outside option is the only option.

With us Bio people it is agreed that the average batches are around 150 lts with perhaps at least half of the batch going for motoring needs. This allows for topping up of the kero with B100 and it is quite safe and in no way detrimental to the burner to do so. However given the harsh winters we had in 2009 and 2010 and given the small amounts we produce at any one time it might make more sense to store the bio indoors in something like a spare steel 205 litre drum. it would be no harm to put a thin layer of insulation around the drum similar to whats used under click flooring to maintain a warmer temperature, this undoubtedly will aid in first time every time ignition. It is also important to make sure that both filters are clean, the external normally 10mm bowl type filter on the supply line coming to boiler is very easy to clean as it is a wash out type filter. there is also a filter on the oil pump held on by four "Allen Studs", remove the cover and the filter is just inside, again wash out in kero and give it a blast of an airline. Be careful when replacing cover and bowl that the rubber seals are in the correct position, otherwise you will have a leak. Dont overtighten.

I changed to a 200 litre steel drum inside my garage/ boilerhouse when I converted to biodiesel. Its arranged on its side on a stand that allows gravity feed to the burner. The distance is about 1 metre from the boiler which I reckon is a bit too close but that does help to keep it warm. I use b90 and had no problems even during the cold spell last year.Il post soon and describe more fully how I converted a Riello 40 series to run on biodiesel.

You can add up to 10% biodiesel to your kerosene without making any adjustments. You might get away with 20% by adjusting the air mix but beyond that you will have to change the nozzle and adjust the pump pressure.The best way to add it is to mix biodiesel and kerosene 50/50 in plastic cubies, shake thoroughly and then pour the mixture into the kerosene tank. Remember to avoid lighting the burner for about 12 hours after adding biodiesel. Adding any extra fuel to a tank can disturb sediment in the bottom of the tank and cause problems.

Thanks For That John, Rightly or Wrongly i read Somwhere on the net that Petrol made Bio Less Viscous so i added a 5% mix to my cubie and tried it, Worked like a dream and Kept burning until it was empty,Would i be doing any damage or should i cease what im doing??

This message has been edited. Last edited by: Tony O'Riordan, May 21, 2012 08:55 AM

wow! Im amazed that only 5% petrol would reduce the viscosity of biodiesel enough to run at kerosene settings. But if it runs then it should be ok. I think 10% would be better and I would run a few cubies through it and then remove the burner from the boiler and have a look at the nozzle and the blast tube. If its very oily or glazed looking the viscosity may still be too high and you should increase the pump pressure. You can buy a pressure gauge in any good plumbing supplies for about 10 euro. If its black and sooty try cutting back on the air. ( note the original position of the air setting so that you can reset it if you have to go back to kerosene.)www.imakebiodiesel.webs.com

This message has been edited. Last edited by: imakebiodiesel, June 04, 2012 06:49 AM

Hi crazy horse have an rgb riello to and will be setting it up on bio soon was wondering if you have any problems since starting it on bio?? And should I make any adjustments apart from what you have said? Cheers Wayne kells Meath

Looking at Riello's website I notice that their burners are now approved for use with biodiesel blends. This means that they no longer use rubber seals. I emailed Riello to find out when they changed over to Viton but they did not have that information but it would seem to be about 2 years ago. It was about this time that they discontinued the biodiesel kit.In my researches into polydiesel I will be buying a viscometer soon. I will be able to use it to test mixtures of bio/kerosene so that it has exactly the same viscosity as diesel. Viscosity is an important property of heating oil because if the viscosity is not right the nozzle will not spray correctly, leading to poor burning. Ill post here when I get this done.www.imakebiodiesel.webs.com

Im not very familiar with the RDB series as the three burners I use are the 40 series.however if you look at the manual it will show you where the air adjustment is and how to reset for diesel/gasoil. the manuals can be down loaded from their website. The pressure gauge is normally screwed into the port for the bleeder.Riello told me that all of their burners manufactured since 2008 are biodiesel approved, ie they have viton seals and that all spares supplied since then have been Viton. However distributors may have had old stock that were sold through 2008, 2009 and even 2010.I had forgotten about testing biodiesel blends for burners but will do it now that you have reminded me. However you wont go far wrong with 80%Bio + 20% kero at the settings for gasoil. Petrol will reduce the viscosity and lower the flashpoint which is good but its expensive and dangerous.Here is a link to Riello RDB manuals http://www.rielloburners.co.uk...section=98&page=1272

This message has been edited. Last edited by: imakebiodiesel, October 11, 2013 05:13 AM

I'm having a few problems with my riello rdb burner, I'm wondering if any if you guys can help? I've been running it on B100 for over a year now through all of last winter with few problems. Recently though it won't fire up on the first fire of the day. I can get it to fire by turning up the pump pressure to around 13bar. Once it's running I turn it back down to the pressure I normally keep it at of 10bar and thereafter it fires just fine for the rest of the day. Unfortunately the next day I have the same problem again on first light up. I've checked a few things, changed the nozzle, took the pump cover off and cleaned the gauze, cleaned the blast tube. Anyone any ideas?

Sounds like the seals on the pump are on the way out. If you are good with pumps you could change them yourself or alternatively get it done. Make sure that the new ones are Viton. Riello genuine spares will be viton since 2008 , but you never know because spares sit for a long time in warehouses. Hydraulic spares suppliers could match up the correct seals in viton.

this is my Riello RDB 1 that runs on B70 as you can see it didnt fire the day before yesterday. I cleaned her up and put on a new nozzle and away we go, heating! what is the problem here? Have i got my settings wrong or is it HMPEs?Can someone advice me on this please